When you’re live-trapping black bears, sedating them with the old syringe-on-a-stick trick, and releasing the bruins back into the wild, there are plenty of rules to keep in mind.

Randy Cross, a wildlife biologist for the Maine Department of Inland Fisheries and Wildlife who serves as the field crew leader in the state’s 36-year research program, knows all the rules. He likely formulated many of them during his 28-year tenure.

One rule: Everyone and everything gets a nickname. Volunteer summer workers are nicknamed. So are bait sites where traps are set up. And bears. And the drugs that are used to temporarily sedate the bears.

That’s why, on Monday, we found “Boss,” or “Boss Hog,” or “Big Dog” (Cross, as the leader, has many nicknames), out in remote Washington County at a bait site called Route 66, which is on the Fat Boy Line of traps. Cross is mixing up a sleeping potion with ingredients he calls “Goofy” and “Super X.” Not too far away, his co-workers “Doc” and “Slick” and “Slingshot” worked other trap lines.

This is just another day in the spring trapping season, during which Cross and two three-person teams trap bears, many of which will be monitored as part of the state’s research project for years to come.

And standing, not so patiently, in the Route 66 snare, was a bear that was sure to be named later.

Which brings us to a second rule. Pay close attention. This is very, very important:

Stay out of the circle.

“See the circle?” the 52-year-old Cross asked, pointing out the clearly defined pattern of churned-up soil that our target bear created in the pre-dawn hours, shortly after finding himself stuck in a wrist snare. “He can reach that tree, and you wouldn’t want that to be you.”

The tree is covered with deep slashes and bite marks, evidence that the bear is none too pleased with his role as an essential subject in the state’s research project.

Cross is right, of course. You don’t want to be the tree.

The bear is lying down — for now — but that will change as soon as Cross moves in with his 8-foot-long syringe pole.

And that bear? He’s big. Really big. And strong?

“He’s more powerful than you’d think,” said Cross, taking a close (but safely distant) look at the bear. “If you didn’t have a jack he could lift the truck up for you.”

That’s when Cross informs you that he’s a little short-staffed this morning, and he needs a little help.

The bear may not want to be drugged, it seems. He may pay too much attention to Cross, and try to avoid being stuck by the hypodermic needle.

And your job, it turns out, is to act like, well, a rodeo clown (without the fancy pants).

“I need you to do what I tell you to,” Cross says. “You’re going to be my hazer. What we’re going to try to do is have the bear charge me, not you.”

But at some point in time, when Cross is good and ready, that equation will change. Then, it’s time for the hazer to make some noise. To move around. To attract the attention of a 364-pound Maine black bear that can jack up your truck, has paws the size of catcher’s mitts, and could take big bites out of you, should he choose.

“You don’t have to know bear language too well to know that when he’s pounding his jaws together like that he doesn’t want you that close,” Cross said.

Which, of course, is not very comforting. Not that it stops Boss Hog from telling you to inch in a little closer.

Just a little closer.

A little closer.

And then, mercifully, it’s all over.

It’s all about the science

The Maine DIF&W maintains three study areas where it puts radio collars on female black bears, then monitors those sows throughout their lives.

Cross said the study has paid dividends: In 1980, the state suspended bear hunting because officials were unsure if hunters were killing too many bears. Now, 30 years later, the bear population is thriving — the population is conservatively estimated at 23,000 bears — and hunters are actually shooting fewer bears each year than the department would like, according to its management plan.

According to the department, the bear study is funded primarily through part of the state’s share of a federal tax on firearms, ammunition and other hunting-related material (75 percent). The remaining 25 percent of funding is generated primarily through the sale of hunting and fishing licenses.

One study is conducted in northern Maine, west of Ashland. Another is just outside of Old Town, in Bradford. And the Down East study area, where Cross and crew are focusing their efforts this spring, centers on an area just northeast of Beddington near the Stud Mill Road.

Each study area is designed to represent a specific kind of habitat that black bears live in elsewhere in Maine.

The more publicized portion of the state’s study effort takes place in the winter, when crews track down the radio-collared females and visit them in their dens. Cubs are enlisted into the research project, and the health of the mother and her young are checked.

In the summer, the research crew focuses on finding new bears that will serve as future research subjects.

“Trapping is kind of a maintenance thing. We’re trapping in the spring because the spring is the most effective six-week period that we can trap,” Cross said. “We’re going to trap for about 6½ weeks this year. We can’t afford to trap any more than that. We used to trap all summer long. We get the most bang for our buck right now [trapping in the spring].”

Cross said males receive lip tattoos and ear tags so that they can be identified in the future, but females are the ones that are of particular interest. Those sows get the full treatment, including radio collars that allow biologists to track them down later.

“[We have] about 108 collared females right now. We usually go into the hunting season with about 110 collared females and hunters will shoot 15 to 17 of them most falls,” Cross said. “Usually we go into the den season with 90, 92, 93 bears [that we’ll visit] in the dens. And in this particular study area’s going to have a mess of ’em this winter. Probably close to 40 bears on the air this winter.”

The Down East study area covers about 300 square miles, and Cross and his crew have set up 98 snares at 68 sites and are pre-baiting several other potential trap sites.

The three crews tend the traps each day, then weigh the bears, fit collars if needed, check temperature and respiration, make some measurements, and collect a hair sample for genetic comparison and a tooth for aging.

The bears remain sedated for about an hour, Cross said, and relatively few suffer problems during the process.

“It’s about one out of 500 or 600 bears in a snare that we actually lose for one reason or another,” Cross said. “And about one out of every 150 [suffers serious injuries].”

Helping to make the research project possible: the work done by temporary summer staffers who work for the department on a volunteer basis.

People like Jared “Slingshot” Mitchell of Rockport and Everett “Slick” Smith of Hope.

Both are senior wildlife majors at Unity College, and both were excited to get some firsthand experience in wildlife biology.

“I’d never done much with bears,” Mitchell said. “I’d never hunted ’em. I hunt everything else, I just never had a chance to. But they’re neat animals. I wouldn’t mind working with them.”

Even as volunteers, the workers are expected to know every aspect of the trapping and handling operation. Either Cross and his former boss, McLaughlin, are on hand to share their expertise, but the volunteers are getting field training they feel will pay off when they enter the job market.

McLaughlin, also known as “Doc,” teaches at Unity and vouched for both volunteers.

And it didn’t take Smith long to learn about Cross.

First came the nickname. Then came the rule. Or maybe it was the other way around.

“The first time you get near a circle, you definitely know what’s going on,” Smith said. “The bear isn’t happy. You’ve just got to make sure you remember everything they say. You don’t get in the circle. Stuff like that.”

Meanwhile back at Route 66

Back in the circle, the 364-pound bear rests peacefully, emitting an occasional deep snore.

The bear is big now, but by hunting season in September, he may have gained another 180 pounds, Cross says. Another bear in the study bulked up from 366 pounds to 545 in just a few short months, he explains.

The bear’s ears are adorned with pink, numbered tags (all the cool bears are getting pierced, you know), and Cross has tattooed an identification number on the bear’s inner lip (ditto).

“This is a bruiser. It’ll be interesting to see how big he gets,” Cross said.

The state record hunter-taken bear was a 680-pounder, Cross said.

After weighing and a few more tests, it’s time to leave the bruin to his slumber, and get out of the woods while the getting’s good.

But first there’s the small matter of a nickname to take care of.

Yes, the bear is identified with a number. And yes, some critics maintain that naming research bears personifies them too much, or disrespects them, or makes them too much like pets.

Cross just thinks it makes them easier to distinguish from each other. And that’s why all the bears in the study have informal (but semi-official) nicknames.

Cross explained that he likes to name bears after people who were present when they were caught for the first time.

Cross looked around the circle. A photographer was present. But she was a she. And she was small.

That just wouldn’t do.

Focusing on his hazer, Cross smiled.

“He’s ‘Big John,’” Cross said.

One more bear

As you might imagine, live-trapping bears is not without its risks to the trappers. Any number of things can go wrong. And any number of those could leave the trapper bleeding.

Cross can tell you all about that. He has been scratched. He has been chased by mother bears whose cubs had been snared.

And he’s been bitten.

Earlier this trapping season, he received his most recent bear bite, when a particular yearling decided he didn’t want to stand still and wait for his hand-administered shot.

“Just missed my watch, but I had my shirt and coat on and it went through my coat,” Cross said. “That was a 70-pounder. The power in their jaws is just staggering. It was a real quick snap. It was almost like, ‘Let go of me.’ I did.”

The bear was one of a pair of twins that have kept trap-tenders running all spring. One brother has been snared five times. The other has been caught three times.

Cross calls the duo “The Rut Brothers.” Their mother was nicknamed “Rut,” after the name of the trap site where Cross first captured her.

On Monday, the Rut Brothers are nowhere to be found.

But at a trap site called Knot, Cross does receive a welcome surprise.

It’s Rut herself, a 17½-year-old sow that has been in the Down East research project since 2004.

“This could be interesting,” Cross said as he circled around Rut, waiting for an opportunity to stick her with the syringe pole.

“We’ll get you right there, sweetie,” he cooed, moving slowly toward the bear. After a few distracting words from the hazer, Rut turned her head. Cross jabbed. Rut reacted like you’d expect, hissing and taking a quick leap toward Cross.

Rut’s progress stopped when the snare pulled taut. With another eight feet of slack, Cross would have been under 246 pounds of Momma Bear.

If, that is, he’d disobeyed his own rule: Stay outside the circle.

“That was a good energetic charge,” Cross said, grinning, as the drugs began to have an effect on the increasingly sedate bear. “But that was probably more impressive from my angle.”

That, it was.

But it was still impressive (or, as we hazers might say, “frightening”) from any angle.

Rut has had a good spring, Cross said, gaining 85 pounds since he last saw her during a den visit on Feb. 10.

“We’ve been feeding her all spring [at the bait sites]. She’s probably eaten five of our beaver,” Cross said, referring to one of the many attractants that are left to lure the bears to the snares.

He’s hoping that she’ll begin producing more cubs than the two Rut Brothers that she gave birth to in 2009.

After Monday’s workday, the crew had successfully trapped and released 82 bears this spring, with 33 of the 43 trapping days completed.

Nobody knows how many more bears will be initiated into the research program before trapping ends in the coming days.

But a couple things are certain.

Cross isn’t done giving out nicknames.

And he’s not yet tired of the job he has had for 28 years.

“I ask the youngsters, after they trap a big bear, ‘Does that make you excited?’ They’re all shaking,” Cross said. “They said it did. And I say, ‘Well, that’s good. Because if it wasn’t, you ought to find a new job.’ Otherwise, lugging bait wouldn’t be worth it.”